Smoke-preventing furnace.



No. 896,411. PATENTED AUG. 18, 1908.

- A. W. PUDDINGTON.

SMOKE PREVENTING FURNACE.

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II In 126 117E07 APPLICATION FILED AUG. 26, 1905.

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A. W. PUDDINGTON. SMOKE PREVENTING FURNACE.

APPLICATION FILED AUG. 26

No. 896,411. PATENTED AUG. 18, 1908.

' A. W. PUDDINGTON. SMOKE PREVENTING FURNACE.

P T I A PLIOA ION FILED AUG 26, 1905 I 4 SHEETS SHBBT 3 Mia. ppm/44 side walls B and a rear wall.

UNITED STATES PATENT oEEIoE.

ARTHUR W. PUDDINGTON, OF CLEVELAND, OHIO, ASSIGNOR TO ROBERT RENNIE, OF TORONTO, CANADA.

SMOKE-PREVENTING FURNACE.

Specification of Letters Patent.

Patented Aug. 18, 1908.

To all whom it may concern:

Be it known that I, ARTHUR W. PUDDING- TON, a citizen of the United States, residing at Cleveland, in the county of Cuyahoga and State of Ohio, have invented a certain new and useful Improvement in Smoke-Preventing Furnaces, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings.

This invention relates to a system of equipping steam boiler furnaces with means for preventing smoke and economizing fuel. The invention also provides a mouth protector for the furnace, increasing the life thereof.

My system is simple, efficient and automatic. It is' easily varied for different conditions and its installation is very durable.

The particular features and their method of cooperation constituting my invention are hereinafter more fully described and their essential characteristics set out in the claims.

In the drawings Figure 1 is a side elevation of a steam boiler and furnace having my invention embodied therein,the view being partly broken away to show the interior. Fig. 2 is a front elevation of the same. Fig. 3 is a vertical section through the smoke space and entrance openings to the fire box. Fig. 4 is a horizontal section through a portion of the furnace just below the boiler. Fig. 5 is a horizontal section of a portion of the furnace just above the grate.

Referring to the parts by letters, A repre sents the boiler, which as shown is of the return tube type. The furnace has the usual The structure has a cast iron front O which provides a smoke space D in front of the boiler and leading to the stack, not shown. fire doors 0 and ash doors 0 The furnace has a grate E, above which is the fire box D, while below it is the ash pit D This much of the construction is of usual form.

Extending upward from the dead plate F between the fire doors and the grate are vertical fines or hollow columns B formed on their sides and rear by courses of bricks and closed on their forward sides by the cast iron front O. The fire doors close the space between these hollow supports B These supports communicate at their lower ends through openings in the dead plate with the ash pit D At their upper ends, the supports carry a grating G. Above this grating is an air chamber D extending across the The front has furnace between the side walls thereof and having at its rear a course of bricks B supported by the grating. At its front the air chamber is closed by the cast iron front C while the top of the air chamber is closed by a suitable plate and a surmounting layerof bricks H. This chamber connects through the grating with the entrance opening and also directly with the fire box by a series of openings 1) through the wall B wherefore air may pass upward from in front of the ash pit through the fines B to the air chamber and discharge downward through the grating and rearward through the openings 1) above the fire, as hereinafter explained.

Located at some suitable point is a tank J adapted to contain petroleum or other hydrocarbon and connected at its lower portion by a pipe K with the boiler. A pipe K leads from the upper portion of this tank to the lower end of the sight feed device L. From the upper end of this device a pipe K leads to the pi e K Joining this pipe K is a i e K whic leads from the steam space of the boiler. Between the sight feed and the pipe K is a valve n-connected with a plunger in the cylinder N. This cylinder is connected by a pipe 16 with the pipe K A s ring a tends to hold the valve n closed'w ile the pressure on the piston from the pipe K tends to open it. K represents a drain pi e leading from the pipe K, but norma y closed.

Leading from the lower end of the pipe K is a pipe P, which is embedded in one of the walls B of the furnace and forms a retort alon side of the fire box, being coiled back and orth on itself as shown at P. Leading from this coil a pipe extends crosswise as at P within the course of bricks H above the air chamber, and extending downward from this pipe P are a number of branch pipes P terminating in nipples p which freely occupy the discharge openings 6 in the wall B and point rearward and downward toward the fire box.

The operation of the system of piping just described, when the steam is admitted from the boiler to the pipe K is that the back pressure of the fluid in the i e P acting against the piston in the cylm er N opens valve 7, admitting oil to the pipe K and oil and steam pass together through this pipe and through the retort P, where the same are heated sufliciently to decompose the steam, making carbon monoxid and hydrogen, which is discharged through the nipples p onto the fire. The force of this discharge draws air through the openings 1) around the nipples. The result is that air and a highly combustible gas is discharged on top of the fire. This discharge may be caused to take place automatically whenever fresh fuel is added to the fire, as hereinafter explained. The operation therefore is to automatically supply to the upper surface of the fresh fuel sufficient air and burning gases to immedi-. ately ignite the fuel and to cause complete combustion of its volatile constituents, thereby preventing the formation of smoke. The jets of gas not only serve to draw in the air and thoroughly mix it with the volatile fuel, but, by being combustible at the temperature of the fire box, not only form a torch to ignite the fuel but give back to the fire the heat which was abstracted in causing the decomposition of the steam and hydrocarbon in the retort. There is therefore no waste of heat such as is the case where a steam et is used to carry in the air,the steam not de composing and burning, but passing off up the stack as superheated steam.

To cause the ection of the combustible gas to be automatic, and to concurrently govern the air, I provide the following mechanism, which is shown and claimed in my di visional ap lication No. 298,907 filed Feb. 1st, 1906. n the steam pipe K is a throttle valve Q, which is shown as connected by a chain 1 with the upper end of a rod 9" connected to a piston in a dash pot R. Leading to this dash pot cylinder is a pipe S connected with water under pressure, as for example, with the city water main. In this pipe S is a valve S arranged to be opened and closed by substantially a half rotation of its stem.

This stem S extends upward as the hingepintle of the fire door 0, being journaled in the stationary ears of the fire door hinge and rigidly connected with the ears. which are rigid with the fire door. When the fire door is closed, this valve S is closed, but when the fire door is opened to admit fuel, the valve is thereby automatically opened. This admits Water under pressure to the hydraulic dash pot R,th e piston of which moving under the force of the Water, opens the throttle valve Q in the pipe K whereupon, as stated,

steam and hydrocarbon are forced through the retort and the resulting water-gas is dischar ed onto the fire.

Be ow thedead plate F area series of dam-' with the lower end of the rod '1- in the dash pot.' The same operation of the dash-pot therefore which causes the injection'of the water-gas opens the air flues so that a suflimay open it.

ciently large quantity of air is discharged with the water-gas through the openings 1), and through the grating G.

Extending from-the dash pot R is adrip pipe r having a valve r After the fire door 1s closed, the action of the injected water gas and air continues until the dash-pot plunger is returned to its normal position,this return being accom lished by the gradual escape of the water from the dash pot cylinder through the pipe r. is regulated by the valve r so that the injec tion of air and water-gas may continue after each firing, for just the length of time necessary to consume those volatile constituents of the fuel, which ordinarily cause smokel This period of time will vary considerably with different fuels a usual period being from two to four minutes.

Adjustable collars r on the rod?" of the hydraulic dash pot may furnish convenient means for limiting the amount of opening of the throttle valve and the air dampers. dash pot rod is shown as having a downward tendency by the weight T on the arm T VVhenthe rod is in its lowermost position, by

reason of this weight, the dampers are closed, and by reason of the chain. g, the throttle valve Q is held in its upper position,- which is its closed position. When the dash-pot rod rises, a weight g on the throttle valve Q This arrangement of chains and weights is simply illustrative and will vary with particular installations. Springs may be substituted for the weights and links for the chains. The important point is that the movement of the dash-pot piston under the influence of the water causes the throttle and the air chambers to open, and the gradual return of that piston causes their gradual closing. I

It will be seen from the above description that the operation is entirely automatic and takes place at the right time and for the right length of time. Moreover, no extra labor is The time of this escape The i required of the fireman in opening the furnace door, such as would. be the case if the swinging of the door directly performed the work of opening the throttle and air dampers instead of simply turning on water pressure to accomplish. that result. I

v The regulation of the flow of hydrocarbon is controlled by the back presssure of the steam and the combustible gases forming in the retort with the result that just the right amount of oil is continually supplied to form such gas. A decrease of steam reduces the gas pressure and this operates to allow the spring n to close the valve n sufficiently to reduce the oil supply. The supply of oil therefore regulates itself automatically.

The nipples p, by being placed in the air openings 6, are continually kept cool, and are t us indestructible instead of being rapidly burned away, as would otherwise be the case.

By having the nipples and the branch pipes supplying them extend downwardly, accumulation of moisture therein is prevented.

The arrangement of air fiues at the sides of the fire doors and the grating, allowing a hot curtain of air to discharge across the entrance opening, form a mouth protector for the furnace, preventing the heat of the fire from becoming wasted by radiation through the furnace front. This construction also keeps the fire room cool, and it is cheaper and more durable than the usual brick arches, which, having no air cooling, rapidlyburn out.

To insure the completest intermingling of the volatile constituents of the fuel and the water-gas and air, I provide a combustion chamber D at the rear of the grate. I make this by building the bridge wallB only a short distance above the grate and providing at the rear of the bridge Wall diagonal, inwardly extending, wing-walls B which extend up to the boiler but leave an open space between them, and at the rear of the wing walls, and separated from them, I provide the baflie wall B, which extends up to the boiler, but is separated at its edges'from the side walls of the furnace. By this means, the hot gases passing over the bridge Walls strike the wing-walls and are deflected into the space between them, and pass back against the surface of the baffle wall, by which they are deflected sidewise against the sides of the furnace, finally passing between the ends of the baffle wall and the furnace walls into the spaceD at the rear of the baffle wall, which leads to the end of the boiler and the return lines therein.

The wing-walls and bafile Wall, together with the upper portion of the bridge wall, and the floor B, which carries the wing-walls, form incandescent surfaces, abstracting the heat from the products of combustion, and insuring the complete combustion of any unconsumed particles passing over the bridge wall. It is to be noted that these incandescent surfaces have the advantage over checker work customarily employed,in that they do not clog with cinders and soot and require frequent cleaning,in fact, they maintain themselves clean by reason of their intense heat. An air conduit D extends from the air chamber at its junction with the outermost fiues B through the furnace walls B and through the bridge wall B Through the back of bridge wall are air openings 1) from the conduit D which furnish additional air to the combustion chamber D In cases where the fire box is very long, additional nipples for the gas may be placed in this air conduit D in the walls B, discharging inwardly and downwardly to perfect the mixing at the rear end of the fire box, which the front nipples may not reach.

When it is desired to draw the fire and therefore allow the fire doors to be opened without injecting the water-gas and air, it is simply necessary to close the hand valve S in the water pipe S. This renders the operation of the valve S idle and prevents the operation of the dash-pot and its consequent action. But' one valve S, connected with one fire door, is necessary. The drawing however shows two valves S in parallel portions of the pipe S and each operated by the corresponding door, and thus an ignorant fireman could not cause smoke by firing through one door only. The same result could be accomplished by a mechanism coupling the doors so that when either is opened, the other is likewise opened.

I claim:

1. In a furnace, a fire box, an air chamber located above and in front of the fire box, Said air chamber having a brick roof, a pipe embedded in said roof and a second pipe extending from the pipe in the roof of the chamber through the chamber and terminating in a nozzle, and means for supplying said pipes with a mixture of steam and air under pressure whereby the air is drawn into the fire box along with the steam and gas.

2. In a furnace, an air chamber, means for feeding through the air chamber a supply of steam and gas, a fire box, a combustion chamber located behind the fire box, said chamber having wing Walls inclined at an angle to the side walls so as to direct the gases toward the central portion of the chamber, a baffle wall spaced from the side walls and located behind the opening between the .wing walls, both the wing walls and baffle wall adapted to become incandescent, thereby insuring the complete combustion of the combustible material.

In testimony whereof, I hereunto affix my signature in the presence of two witnesses. ARTHUR W. PUDDINGTON. Witnesses:

ALBERT H. BATES, N. L. BnEsNAU. 

